Cirrus Logic AN339 - Manual (Page 11)

AN339
AN339REV1
AN339REV1 11
on the CDB4398 for all measurements sourced by the CS8416. Refer to the CDB4398 and CDB8416 data
sheets for more information on each evaluation board.
Block diagrams of each test set-up are shown in Figure 32 and Figure 33 .
An Audio Precision
®
(AP) SYS-2722 high-performance audio analyzer was used to generate the digital in-
put signals for the receivers and to measure the analog output signals from the CS4398. Agilent
®
E3631A
power supplies were used to power the evaluation boards.
A Tektronix
®
DPO7054 oscilloscope with JIT3 software was used to measure the jitter signal of the CS8414
and CS8416’s recovered master clocks. The software was configured to generate phase noise plots with no
averaging applied to produce the figures shown in
Section 5 . The phase noise integration function was used
to calculate the baseband jitter values shown in Table 2 .
For each plot shown, the blue traces represent data taken using the CS8414 as the clock and data source,
the green traces with the CS8416 and PDUR=1 as the clock and data source, and the red traces with the
CS8416 and PDUR=0 as the clock and data source. For clarity, only AOUTA is shown in the plots; no no-
table differences were seen between the CS4398 output channels.
CDB4398
CS4398
U9
AOUTA
AOUTB
Tektronix
Oscilloscope
AP
SYS-2722
BALANCED
ANALOG
INPUT
AP
SYS-2722
S/PDIF
OUTPUT
J18
J27
J17
S/PDIF
INPUT
CS8414
U2
J8 J10 J9 J6
Agilent E3631A
Power Supply
GND +18V -18V +5V
Figure 32. CS8414 Test Setup
CDB8416
CS8416
J9
U19
CDB4398
CS4398
J12 U9
PC
M
I N
P
U
T AOUTA
AOUTB
Tektronix
Oscilloscope
J18
PC
M
OU
T P
U
T
AP
SYS-2722
BALANCED
ANALOG
INPUT
AP
SYS-2722
S/PDIF
OUTPUT
J18
J27
J3 J4
S/PDIF
INPUT
J8 J10 J9 J6
Agilent E3631A
Power Supplies
+5V GND GND +18V -18V +5V
Figure 33. CS8416 Test Setup